Au complexes

With a tridentate ligand Au(terpy)Cl3.H20 has, in fact, AuCl(terpy)2"1" with weakly coordinated chloride and water while Au(terpy)Br(CN)2 has square pyramidal gold(III) the terpyridyl ligand is bidentate, occupying the axial and one basal position [124]. Macrocyclic complexes include the porphyrin complex Au(TPP)Cl (section 4.12.5) cyclam-type macrocyclic ligands have a very high affinity for gold(III) [125],... 

Square planar coordination is general in these in the tris-complexes Au(S2CNR2)3, it is obtained by two dithiocarbamates being monodentate (the third is, of course, bidentate) [131], Such planar coordination in [Au(S2CNEt2)2]+SbF6 involves Au—S distances of 2.316-2.330 A [132]. 

Table 1.2 gives the Au Au distances, and Au Au Au and N-Au-N angles for several homobridged tetranuclear Au(I) complexes and tetranuclear gold amidi-nate complexes. Similar structural arrangements have been found in the tetrameric l,3-diphenyltriazenidogold(I) complex, [Au(PhNNNPh)]4 (Au Au = 2.85 A) [21],... 

These complexes show considerable in vitro cytotoxic effects against various tumor cell lines [70, 71[. Moreover, the cationic complexes [Au(N,N, N")Cl[Cl are able to intercalate into ct DNA [71[. Gold(III) amidate complexes of histidine containing... 

Adventitious water is responsible for the formation of the dimeric hydroxo complex 31 obtained by reaction of AuCb with 1,4-dilithiotetraphenylbutadiene in ether solution [97[. The hydroxo-bridged complex [Au(C6H4N02-2)2( i-0H)[2 (32) was obtained either by reaction of Na[Au(C6H4N02-2)2(0Ph)2] with traces of water in CH2Cl2/n-hexane solution or by treatment of the dichloroaurated complex with NaOH [98[. The crystal structure of 32 2Et20 shows that it is a centrosymmetric... 

Treatment of the cyclometallated complexes [Au(N,N,C)Cl][PF6] [N,N,CH = 6-methylbenzyl- (a) or 6-(l,l-dimethylbenzyl)-2,2 -bipyridine (b)] [20] with KOH or Ag20 in aqueous media affords the hydroxo complexes [Au(N,N,C)(OH)][PF6] (36) in fairly good yields [45b, 101] these are air-stable white solids, quite soluble in water and in many organic solvents. When refluxed in anhydrous THF they condense to give the oxo-bridged complexes [Au2(N,N,C)2( J--0)] (37) (Equation 2.10 in Scheme 2.5) which, in turn, can be obtained by a different route [102] (see Section 3.2) the reaction can be reversed by refluxing the 0x0 complex in water. 

The bis amido complex [Au(bipy)(NHC6H4N02-4)2][Pp6] (43) has been similarly obtained by reaction of 40 with p-nitroaniline in acetone solution (Equation 2.14 in Scheme 2.6) [45b]. Complex 40 promotes the stoichiometric oxidation of various amines different from p-nitroaniline. Azotoluene is the main organic product of the... 

The hydroxo complexes [Au(6-Rbipy)(OH)2], postulated as intermediates in the formation of 44c-i, are not isolated nevertheless, in all the mass spectra (FAB conditions) a weak peak is found corresponding to these species. Unchanged 44c-i are quantitatively recovered from the reaction with aqueous solutions of HX (X = BF4 or PFfi) neither dihydroxo complexes similar to those observed in the vapor phase, nor hydroxo bridged dimers are obtained [25]. 

Reaction of HAuCU with the dipeptide glycylalanine (H-Gly-Ala-OH) and the tripeptide glycylalanylalanine (H-Gly-Ala-Ala-OH) gives the corresponding complexes [Au(Gly-Ala-0)Cl] (66) and [Au(Gly-Ala-Ala-O)] (67) where the peptides are coordinated to gold through — NH2, amide(s) and G02 groups in a near square... 

Figure 3.1 Drawing of the identical pairs of molecules of the complex [Au(C6F5)(tht)] alternatingly rotated.

The reaction of methylene bis(dialkyldithiocarbamates) with [Au(C6F5)(tht)j leads to the complexes [ Au(C6F5) 2 CH2(S2CNR2)2 ] [43] (R = Me, Et, n-Bu, Bz). The NMR resonances of the bridging methylene groups in the complexes are observed at lower field than that in the free ligand and some modification of the C=S stretching is observed. 

Depending on the R group, this reaction could lead to the formation of gold(I) isocyanide complexes that behave as liquid crystals. Thus, complexes [Au(C6F5) (C = N(QH4)OCioH2i-p)] and [Au(QF5)(C = N(QH4)OCnH2n + rP)] [64] where n = 4, 6, 8, 10 and 12 show this behavior. All of these complexes are mesomorphic and behave as liquid crystals showing a nematic (N) phase when the isocyanide has a... 

When the Au(I) complex [Au(CGF5)(tht)j reacts with lithium l-methylimidazol-2-yls the organic compound is protonated or alkylated and the carbene complexes are obtained [67] (see Figure 3.3). 

The reaction of the complex [Au(C6E5)(Ph2C=N—N=CPh2)] with 2,6-dimethyl-phenylisocyanide (CNXy) leads to the formation of [Au(CGF5)(CNXy)] [50] by displacement of the ligand. The IR shows an absorption at 2214 cm that is due to the V(CN) of the coordinated isocyanide. 

The reaction of the [Au(C6F5)(tht)] with 2-amino-4,5-dihydrothiazole (2-amt) yields the complex [Au(CgF5) (2-amt)] [47]. When [Au(C6E5)(tht)] reacts with N(H)=CPh2 the complex [Au(C6F5) N(H)=CPh2 ] [48] is obtained. The structure of this complex shows that two molecules of the complex are associated in an antiparallel manner with Au(I)-Au(I) interactions of 3.5884(7) A. 

When the Au(I) pentafluorophenyl complex [Au(C6F5)(tht)] reacts with a phosphine the tht ligand is easily displaced to give the corresponding phosphine complexes. This was the method employed to obtain all the following complexes. 

The reaction of the gold(I) complex [Au(C6F5)(tht)j with the water soluble phosphine l,3,5-triaza-7-phosphaadamantane (PTA) gives the complex Au(C6F5) PTA] [28]. 

The reaction of methyl dithiocarbamates with [Au(QF5)(tht)] leads to the formation of the neutral complexes [Au(C6F5)SC(SMe)NHR] [61], R = p-MeC6H4, o-MeC6H4, p-MeOC6H4 or 3,5-Me2C6H3. The H NMR shows that the dithiocarba-mate is S-coordinated and the IR spectra shows the absorption of the Vjnh)-... 

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